<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>标签选择器 类选择器</title>
<style type="text/css">
.red{color:red;}
.green{color:green;}
.font22{font-size:22px;}
h2{text-decoration:underline;}

</style>
</head>

<body>
<h2 class="red">二级标题文本</h2>
<p class="green font22" >段落一文本内容</p>
<p class="green">段落二文本内容</p>
<p>段落三文本内容</p>
</body>
</html>
